GV Settings have to be on maximum visual range otherwise you don't see GV's at a distance, so attempting to remove the "trees" from a distance only means you can't see a GV either so its pointless attempting to run at the lowest graphic settings - however I do not have the smooth ground settings or high res packs due to a laptop that easily overheats which causes it to crash due to the temperature.
What I see is what everyone else see's, its just not on a high resolution or "eye candy", he knew where I was, film you can clearly hear at least 20+ ricochets so I'm quite sure he clearly seen me on his end - rather he just wasn't able to kill me.
Hopefully in a few weeks I can get my new PC, its degrading enough when you can't even tell the angles of hills in a GV, which cause me to flip a GV 4-5 times a day because the hills are a light green color which match the ground surface, so judging the angles can be brutal.
When GVing I've noticed a few things... Mountains aren't always opaque, trees and other flora aren't always there, and what the other guy sees is more important than what you see. I've been behind hedge rows where the only thing I see is round after round going through the hedge row and hitting me. From other guys film, he was actually lobbing over the top, however due to how the game computes things, round is on a flat tragectory on my screen. I've been behind mountains or hills where I know there was no way someone could see me, only to have someone lob a round over the top or get an extremely narrow angle for a shot. I've seen on my end how this happens, and it's because sometimes you can just see things through mountains (like the sun).
Finally, in regards to graphics settings:
Turning down your vis range or your object range will only make it harder to take long shots, all objects are still there, now you just can't see them. There are objects that 'aren't there'. These are the same things you drive through. Turn off 'bump map terrain' and hit ctrl-f4 when GVing, you'll get rid of the clutter, and focus your graphics to loading what you can actually see in a GV. This is about the biggest advantage you can get by tweaking game settings.